2004 GMC SIERRA light

{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. See
Parking Brake on
page 2-48
.
NEUTRAL:Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-54orTowing
Your Vehicle on page 4-53for more information.Indicator lights in the switches show which setting your
transfer case is in. The indicator lights will come on
brie¯y when you turn on the ignition and one will stay on.
If the lights do not come on, you should take your
vehicle to your dealer for service. An indicator light will
¯ash while the transfer case is being shifted. It will
remain illuminated when the shift is complete. If
for some reason the transfer case cannot make a
requested shift, it will return to the last chosen setting.
If the SERVICE 4WD light stays on, you should take
your vehicle to your dealer for service. See
Service on
page 5-3for further information.
Shifting into 4HI or AUTO 4WD
Press and release the 4HI or AUTO 4WD switch. This
can be done at any speed (except when shifting
from 4LO), and the indicator light will ¯ash while shifting.
It will remain illuminated when the shift is completed.
Shifting into 2HI
Press and release the 2HI switch. This can be done at
any speed (except when shifting from 4LO).
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Shifting into 4LO
To shift to 4LO, the ignition must be in RUN and the
vehicle must be stopped or moving less than 3 mph
(4.8 km/h) with the transmission in NEUTRAL (N). The
preferred method for shifting into 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the 4LO switch. You must wait for the
4LO indicator light to stop ¯ashing and remain
illuminated before shifting your transmission in gear.
Notice:Shifting the transmission into gear before
the 4LO indicator light has stopped ¯ashing
could damage the transfer case. To help avoid
damaging your vehicle, always wait for the
4LO indicator light to stop ¯ashing before shifting
the transmission into gear.
It is typical for your vehicle to exhibit signi®cant
engagement noise and bump when shifting between
4LO and 4HI ranges or from NEUTRAL with the engine
running.
If the 4LO switch is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light will ¯ash for
30 seconds and not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds
the transfer case will shift to 4HI mode.
Shifting Out of 4LO
To shift from 4LO to 4HI, AUTO 4WD or 2HI your vehicle
must be stopped or moving less than 3 mph (4.8 km/h)
with the transmission in NEUTRAL (N) and the ignition in
RUN. The preferred method for shifting out of 4LO is to
have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the 4HI, AUTO 4WD
or 2HI switch. You must wait for the 4HI, AUTO 4WD or
2HI indicator light to stop ¯ashing and remain illuminated
before shifting your transmission into gear.
Notice:Shifting the transmission into gear before
the 4LO indicator light has stopped ¯ashing
could damage the transfer case. To help avoid
damaging your vehicle, always wait for the
4LO indicator light to stop ¯ashing before shifting
the transmission into gear.
It is typical for your vehicle to exhibit signi®cant
engagement noise and bump when shifting between
4LO and 4HI ranges or from NEUTRAL with the engine
running.
If the 4HI, AUTO 4WD or 2HI switch is pressed when
your vehicle is in gear and/or moving, the 4HI,
AUTO 4WD or 2HI indicator light will ¯ash for
30 seconds but will not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N).
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Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Make sure the vehicle is parked so that it will
not roll.
2. Set the parking brake.
3. Start the vehicle or turn the ignition to RUN.
4. Connect the vehicle to the towing vehicle.
5. Put the transmission in NEUTRAL (N).
6. Shift the transfer case to 2HI.
7. Simultaneously press and hold the 2HI and
4LO buttons for 10 seconds. The red NEUTRAL
light will come on when the transfer case shift
to NEUTRAL is complete.
8. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
9. Turn the ignition to OFF.
10. Place the transmission shift lever in PARK (P).
11. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (2HI, 4HI, AUTO 4WD or 4LO).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. Release the parking brake.
6. You may start the engine and shift the transmission
to the desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter the
shift protection mode. This will protect the transfer case
from possible damage and will only allow the transfer
case to respond to one shift per 10 seconds. The transfer
case may stay in this mode for up to three minutes.
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g(4LO):This setting also engages your front axle to
give you extra traction. You may never need 4LO. It
sends the maximum power to all four wheels. You might
choose 4LO if you were driving off-road in sand, mud
or deep snow and climbing or descending steep hills.
Indicator lights in the switches show you which
setting you are in. The indicator lights will come on
brie¯y when you turn on the ignition and the last chosen
setting will stay on. If the lights do not come on, you
should take your vehicle in for service. An indicator light
will ¯ash while shifting. It will remain illuminated when
the shift is completed. If for some reason the transfer
cannot make a requested shift, it will return to the
last chosen setting.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. See
Parking Brake on
page 2-48
.
NEUTRAL:Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-54orTowing
Your Vehicle on page 4-53for more information.
Shifting from 2HI to 4HI
Press and release the 4HI switch. This can be done at
any speed, and the front axle will lock automatically
with some delay.
Shifting from 4HI to 2HI
Press and release the 2HI switch. This can be done at
any speed, and the front axle will unlock automatically
with some delay.
2-45

Shifting from 2HI or 4HI to 4LO
To shift from 2HI or 4HI to 4LO, the vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with the
transmission in NEUTRAL (N). The preferred method
for shifting into 4LO is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the
4LO switch. You must wait for the 4LO indicator light to
stop ¯ashing and remain illuminated before shifting
your transmission into gear.
Notice:Shifting the transmission into gear before
the 4LO indicator light has stopped ¯ashing
could damage the transfer case. To help avoid
damaging your vehicle, always wait for the
4LO indicator light to stop ¯ashing before shifting
the transmission into gear.
If the 4LO switch is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light will ¯ash for
30 seconds and not complete the shift unless your
vehicle is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). The transfer case
will shift to 4HI while waiting to complete the shift.
Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2HI, your vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N). The preferred method
for shifting out of 4LO is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the 4HI
switch. You must wait for the 4HI indicator light to
stop ¯ashing and remain illuminated before shifting your
transmission into gear.
If the 4HI switch is pressed when your vehicle is in gear
and/or moving, the 4HI indicator light will ¯ash for
30 seconds but will not complete the shift unless the
vehicle is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N).
Shifting into NEUTRAL
To shift the transfer case to NEUTRAL, ®rst make sure
the vehicle is parked so that it will not roll:
1. Set the parking brake.
2. Start the vehicle or turn the ignition to RUN.
3. Connect the vehicle to the towing vehicle.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to 2HI.
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6. Simultaneously press and hold the 2HI and 4LO
buttons for 10 seconds. The red NEUTRAL light
will come on when the transfer case shift to
NEUTRAL is complete.
7. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
8. Turn the ignition to OFF.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (2HI, 4HI, or 4LO).4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. Release the parking brake.
6. You may start the engine and shift the transmission
to the desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter the
shift protection mode. This will protect the transfer case
from possible damage and will only allow the transfer
case to respond to one shift per 10 seconds. The transfer
case may stay in this mode for up to three minutes.
2-47

Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime will activate and the warning light will ¯ash
when the parking brake is applied and the vehicle
is moving at least 3 mph (5 km/h) for at least
three seconds.To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking
brake symbol, to release the parking brake.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Verify that
the parking brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and are parking on any hill,
see
Towing a Trailer on page 4-70.
2-48

Automatic Dimming Rearview Mirror
with OnStar
ž, Compass and
Temperature Display
Your vehicle may have this feature. When on, an
automatic dimming mirror automatically dims to the
proper level to minimize glare from lights behind
you after dark.
The mirror also includes a dual display in the upper
right corner of the mirror face. The compass reading and
the outside temperature will both appear in the display
at the same time.
P(On/Off):This is the on/off button.
Temperature and Compass Display
Press the on/off button, located to the far left, brie¯y to
turn the compass/temperature display on or off.
If the display reads CAL, you will need to calibrate the
compass. For more information on calibration, see
below.
To adjust between Fahrenheit and Celsius do the
following:
1. Press and hold the on/off button for approximately
four seconds until either a ¯ashing ÉF, or ÉC
appears.
2. Press the button again to change the display to the
desired unit of measurement. After approximately
four seconds of inactivity, the new unit will be locked
in and the compass/temperature display will return.
If an abnormal temperature reading is displayed for an
extended period of time, please consult your dealer.
Under certain circumstances, a delay in updating
the temperature is normal.
2-55